Speedometer



' C. CARSON.

SPEEDOMETER.

APPLICATION FILED JUNE 10. 1915. RENEWED AUG. 6, 1919.

Patented Oct. 21,1919.

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SPEEDOMETER. APPLICATION FILED JUNE 10. 1915. RENEWED AUG. 6, I919.'

1,319,204. Patented Oct. 21,1919.

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SPEEDOMETER.

APPLICATION FILED 1UNE10 I 1915. RENEWED AUG. 6. m9.

Patented Oct. 21, 1919.

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,4 TTOR/VE YJ' UNITED srn'rns PATENT OFFICE.

CLARENCE CARSON, OF N ROCHELLE, YORK, ASSIGNOR T0 H. W. JOHNS- I MANVILLE COMPANY, A CORPORATION OF NEW YORK.

, SPEEDOMETER.

Specification of Letters Yatent. PatentedOct. 21, 1919.

Application filed June 10, 1915, Serial No. 33,254. Renewed August 6, 1919. Serial No. 315,788.

To all whom it may concern Be it known that I, CLARnNoE'CARsoN, a citizen of the United States, and resident of New Rochelle, in the county of Westches ter and State of New York, have in-.

vented certain new and useful Improvements in Speedometers, of which the followjerking movements and the invention parstock inclosing casings of different standard ticularly relates to improvements in unitary inserts constituting the mechanical part of such instruments.

It has been usual in this art-to supply speedometers in numerous sizes and to construct the different mechanical elements thereof proportionate to the different sizes of instruments, each size or type being designed and constructed complete in itself.

It isone of the objects of my invention to construct the mechanical parts together with a carrying frame of one standard size forming a unit which can be carried in stock. With these units there is also carried in sizes and reading dials of diiferent'standard sizes. provided with scales of. different ranges, each designed to co-act with the With this instock, it is possible, when an order is received for a certain character of instrument, to take one of these mechanical units adjust the same for installation .in the required size casing or to fit the required size dial or scale and in this way any size or type of instrument can be supplied from stock provided the required size casing or type of dial is available.

structure and properly mounting the same This I am enabled to attain with the device hereinafter described, simply by shifting a minor part of the mechanical in the desired type or size of easing.

Speedometers of the centrifugally actuated type are usually inaccurate especially at low speeds and accordingly it is a further object of the inventiontd provide a.

construction for attaining an accurate speed reading irrespective of the speed of the driving parts and to provide such an instrument which will at the same time be capable of indicating an accurate reading over a relatively long range of speeds.

It is among the other objects of the invention to provide a structure designed so as to permit of a delicate calibrating of the same; so that the dial indicator shall/ be free from any tremulous or jerky movefree from backlash Or other loose connections andso that there will be a minimum of friction or wear.

Various other objects and advantages -.of the inventionwill be in part obvious from an inspection of the accompanying draw ings and in part will be more fully set forth in the following particular descripment; so that the moving parts shall be tion of one form of mechanism embodying myinventlon, and the inventlon also consists in certain new'and novel features of construction and combination of parts hereinafter set forth and claimed,

Referring to the accompanying drawings:

Figure 1 is a front view of a preferred embodiment of my invention with the dial removed and certain parts broken away to show internal construction 1 Fig. 2 is a longitudinal sectional view taken on the line 2-2 of Fig. 1 looking in the direction indicated by the arrow;

Fig. 3 is a portion of the governor of Fig. 2 shown in action;

Fig. 4 is a plan view looking down on'v the device and with portions ofthe casing and supporting frame in sect on;

Fig. 5 is a view similar to Fig.1 showmg the mechanical unit mounted in a casing larger than the casing shown in Fig. 1;*-- Fig. 6 is a front elevation of the complete device shown in either Figs. 1* or 5; Fig. 7 is a horizontal sectional view taken on the line 77 of Fig. 6 looking in the direction. indicated by the arrows; and

Fig. 8 is a view'in elevation of the rear side of the adjustable dial actuating cam. In the following description and in the claims, arts will be identified by specific names fbr convenience of expression but they are intended to be as generic in their application to similar parts as the art Wlll permit. v In the drawings there is shown a mechanic'al unit including a su 'iporting frame 10 of any convenient configm-ation, best suited for lnstallation 1n the diflerent styles of casings and shown to be a circular band provided with laterally extendingand oppositely disposed supports 11 and 12 cast integral therewith and constituting a spacing means for localizing the units in a containing casing. The ends of each of the supports 11 and 12 are provided with tapped holes adapted to receive respectively the pairs of screws '13 and 11, the former of which are designed to pass through the rear wall of the containing casing hereinafter described to fasten the units thereto and the latter of which are designed to fasten the mounting plate 15 demountably in position at the front of the completed instrument and spaced from the frame 10. The frame 10 is provided at a point therein intermediate the supports with a hub 16 having an annular opening 17 diametrically disposed relative to the circular frame in which opening is positioned an end thrust bearing member 18 for a driving shaft 20. This bearing member also constitutes aball bearing cap providing a runway in which is contained anti-friction devices 19, such as ball-bearings, positioned between the runway and the cone shaped end of the shaft 20. Hubs 21 and 22 are provided on the frame 10 diametrically positioned opposite the bearing 18, the latter of which hubs project externally of the outlines of the frame lO'and is provided with a reduced threaded portion 23 by means of which the device may be mounted in position or by means of which a container of the driving element may be attached. The hubs 21 and 22 form in effect a continuous cylinder, the bore 24 of which is internally threaded and in which is adjustably mounted a bearing block 25; through which extends the shaft 20. The outer end of the shaft-extends beyond the hub 22 and is designed to be operatively connected to any member the speed of which is to be ascertained. This bearing block 25 constitutes an end thrust bearing for limiting the movement of the shaft away from the end thrust bearing 18 and for this purpose is provided with a runway in which is positioned anti-friction devices 26 such as roller bearings, which are moved by the-adjustment of the bearing block 25 into bearing engagement with the shoulder 26 formed on the shaft 20. In order to adjust and lock the bearing block in place, the other end thereof is provided with screwdriver slots 27. The block is locked in position by a lock-nut 28 also provided with screw-driver slots 29; slots 27 and 29 being designed so as to be simultaneously engaged by j a compound screw-driver insertible through the bore of the hub 22. The driving shaft 20 constitutes a governor shaft and is provided with a centrifugally actuated governor consisting of weights 30 arranged in a circle. These weights may be of any shape and number and in the form illustrated are shown to be provided adj acent the pivotal connection provided by the pin 33 with a stop 34 adapted to engage the other link and thus limit the outward throw of the weight 30. The links 31 are pivotally secured by means of ins 35 to a collar 36 fixed to the governor s aft 20 adjacent the end thrust bearing member" 18. The links 32 are pivotally secured by means of pins 37 to a collar 38 fixed to the runner 39 which is slidably mounted on the governor shaft 20 and which constitutes the speed controlled member of the device. A relatively heavy tension spring 40 and a rel atively light tension spring 41 are disposed in orderbetween the stationary collar 36 and the runner 39 with their adjacent ends bearing on opposite sides of a collar 42 slidably mounted on the shaft 20. The runner 39 is in the form of a sleeve having a relatively lon bearing on the shaft and provided wit a pair of laterally projecting disks 43 extending perpendicular to the axisof movement of the same and spaced apart longitudinally of said axis to form an annular runway therebetween. The bore of said sleeve is enlarged intermediate its ends which bear on the shaft to provide an annular pocket 44; and the sleeve is provided with air vents 45 for permitting the escape of air from said pocket during the sliding movement of the runner.

The indicator actuating mechanism is carried on the mounting p ate 15 and is removable therewith from the frame 10 as a unit. This mechanism comprises a pair of shafts journaled in the mounting plate 15 and in the bridge plate54 affixed to the rear face of the mounting plate. One of the shafts 51 projects rearwardly through the bridge plate, which projected portion has a crank arm 48 adjustably fastened thereto by means of a collar 52 fastened to the shaft by a set-screw53. The crank includes an arm or stud 46 provided with a rounded head 47 adapted to be inserted in the runaway 74 so that the movement of the runner will rock said crank and its shaft. The shaft 51 is enlarged between the plates 14 and 54 to prevent longitudinal movement thereof and the portion thereof adjacent the plate 15 has a sector gear 55 adjustably crank arm.

notched extension 49 depending from the A stop 50 projects rearwardly from the bridge plate and constitutes a means for limiting the rocking movement of the crank. The shaft 57 extends forwardly through the mounting plate 15 and constitutes the indicator actuating shaft. through an opening in the dial plate 62 which dial plate is provided with a scale 76 arranged in an arc with the opening 75 concentrically disposed relative thereto. The indicator or pointer 63 is fixed to the shaft 57 by means of a hub. 64 and is arranged to move relative to the scale as is usual with devices of this character. A p lley 58 is fixed to theshaft. 57 between t 1e plates 15 and 54 and a spring 59 is wound about the pulley with one end secured thereto and the other end secured to the bridge plate 54 by passing the free end of the sprlng through a small aperture 77 in -the end wall of the bridge plate. In the type of instrument illustrated in Figs. 1 and 2, the mechanism-containing casing 65 is of a size designed so'that the mechanical unit hereinbefore described shall have a snug fit therein. One side of the casing, for convenience referred to as the bottom side, is provided with a recess 66 opening from the front edge thereof to receive the hub 22 which extends therethrough. Opposite sides of the cylinder formed by the hubs 21 and 22 are provided with grooves 78 into which the edges forming the recess 66 have a sliding fit to fix the unit in place in the casing. If desired, the instrument may be supported by a back plate .68 which is shown attached to the casing by screws passing therethrough into spaced bushings 67- formed in the back plate. This back plate is also provided with screw holes 69 constituting an additional means for fastening the instrument inany desired position.

In the modifications illustrated in Figs. 4 and-'5, the casing is shown to be-of a larger diameter designed to accommodate a larger dial plate having a scale of correspondingly larger diameter; With a scale of this type it isobvious that the indicator actuating shaft must be moved so that it will rotate about an axis concentrically disposed relative to the arc of the scale. For this purpose the mounting plate and bridge late are provided with a plurality of a ined.

small holes. 70 constituting journal bearings for the indicator shaft. These bearings are concentrically. dlisposed ndlative to the axis of rotation of the shaft 51 and to the outside of the sector gear. Two of these bearings are illustrated in the drawings, but it is of course obvious that as many of these bearings may be provided as there are different size of dials to which themechanical units are designed to cooperate.

Thisshaft is designed to extend with a glass retaining ring 71 for holding the front glass face 72 in position.

In operation, let it be assumed that a mechanical unit ofrthe class'described is car ried in stock together with dials of different sizes and with the indicator shaft opening in the dials differently positioned relative to the recess 66 in the casing. When an order is received for a certain size speedometer, the casing of that required size is assembled with one of the mechanical units. The indicator actuating shaft 57 is adjusted in the,particular bearing 7 0 which will register with the opening in the dial plate when the parts are assembled and the unit is inserted in the casing with its grooves 78 containing the edges of the casing at the recess 66. f-When the parts are assembled the set screw 53 is loosened and the crank adjusted on the shaft 51 until the head 47 has a slight bearing engagement upon one of the disks 43. The sector gear 55 is adjusted on the shaft 51, if such an adjustment is necessary to-preserve the meshing of the device is calibrated to fit the particular dial used, which calibrating may be attained roughly by the adjustment of the spring 61 or a more refined calibrating may be atsame with the pinion 56. If necessary the tained by drawing more or less of the spring 59 through the opening in the bridge plate.

the shaft 20 will cause the weights 30 to move outwardly under the centrifugal force developed, which weights will act through the links causing the runner to'approach the relative stationary stop. The initial portion of this sliding movement of the runner, that is, the movement at low speed of the shaft, will be resisted by the relatively weak tension spring'41 and the continued movement of the runner will gradually bring into play the resistance of the relatively heavy spring 40 thus progressively increasing the resistance to the movement of the runner with the increase in speed of the actuating element. This movement of the runner will continue until such a speed is attained, such as will the shaft 51 is transmit-ted through the gearing formed by the sector gear and pinion to correspondingly rock the indicator shaft 57 which in turn swings the pointer over the face of the dial plate 52 to indicate on the scale thereof the speed readings.

Should the speed of the shaft 20 decrease, the springs l0 and 4:1 in turn exert their ten sion to return the runner into its normal position shown in Fig. 2 and the spring 61 acts in cooperation with the spring 58 to return the indicator actuating mechanism into its initial cost of construction and these different units may be made to fit the desired size casing, merely by shifting the position of the indicator actuating shaft. This stock unit may be calibrated quickly and conveniently to fit any desired scale within the range of the instrument.

As all of the indicator actuating mechanisrns are carried by-the mounting plate, this plate and its attached parts may be readily removed as a unit this providing ready access to the parts carried thereby. In this way springs of different tension may be substituted conveniently for the springs originally assembled therewith and cleaning and repairing of the several parts is facilitated. The indicator is held fixed in its speed controlled position on the dial and is not affected by the vibration of the support carrying the instrument. This renders the instrument particularly adapted for accurate speed reading when used on a motor vehicle or on other vibrating machinery. The

adjustment ,of the end thrust bearing per mits the mounting of the shaft in position fixed against longitudinal movement and the anti-friction means permits the easy rotation of the shaft. The bearing block 25 maybe adjusted from time to time to take up -wear (in the shaft without demounting the parts as access is provided to the same through the open end of the bore 24. All loose connection between theseveral parts is eliminated as the spring 61 is of a tension sufficient to maintain the head 47 continuously in firm engagement with the runner 39 and the spring 59 maintains the teeth of the sector gear and pinion continuously in bearing engagement with each other.

Ease of movement between the parts is attained further by reducing thefriction between the runner and shaft. \Vhile the bearing of the crank upon one side of the projecting flanges 43 has a tendency to cant the runneron the shaft, this actionis minimizedby the centering of the spring engaging the upper end of therunner and by the spacing ofthe end bearings of the runner in their engagement with the shaft. Providing the air-vents 45 between the ends of the runner bearing on the shaft permits air to escape from between the runner and shaft thus facilitating the sliding action of this member. The ease of operation of this device is enhanced by the particular construction of the governor weights. The vibration of the casing has little, if any effect upon these weights as any vibratory movethis movement has little, if any efiect, upon the speed controlled member 39. It is obviously within the scope of this invention to fix the weight 30 to the link 32 and the drawings may be so 'read.

The spring 59 may be made as delicate as desired, thus providing for a refined calibrating of the instrument by varying the tension of this spring. As the spring engages the last element of the indicator ac tuating mechanism, it positions this adjust-- ment at the most vital point of the mecha-- nism.

IVhile I have shown and described, and

have pointed out in the annexed claims, cer- H tain novel features of my invention, it will be understood that various omissions, substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. 7

Having thus described my invention, I claim:

1. In a device of the class described, the combination with a dial, provided with a scale arranged in an arc, said dial having an opening therethrough concentrically disposed relative to said scale, of a mechanical unit adapted to be assembled with said dial to provide a complete instrument, said unit including a support provided with a plurality of bearings, one of which is adaptedto' register wit-h said opening when the dial is dial openings difi'erently positioned, said unit including speed controlled mechanism comprising an indicator shaft shiftable rela-..

tive to the unit to extend through the difi'erently positioned 0 enings' in the different dials, drivingmec anism mounted in the unit in relatively fixed position and a shiftable connection between said shiftable shaft and said driving mechanism,

3. In a device of the class described, the combination with a casing provided-with means at one .side for attaching the same to mechanical units of different sizes relative to the size of said casing, of a mechanical unit of one of said different sizes adapted to be inserted into said casing and provided with means co-acting with said first named means for fastening the same in place in fixed relation thereto, said casing being'provided with an opening and said unit being provided with mechanical parts, one of which parts project through said openings and said partbeing adjustable in the unit to register with the opening in the casing.

4. In a device of the class described, the combination with a mechanical unit having a driving element and a driven element projecting therefrom and speed controlled mechanism operatively connecting said elements, one of said elements being shiftable into different positions in said unit, a unit containing casing adapted to be assembled with said unit to form a complete instrument, said casing being provided with fixed spaces adapted to accommodate said elements when the shiftable element is in that one of itsdifl'erent positions designed to be accommodated in the spaces thereof.

5. In a device of the class described, a mechanical unit constituting a complete article of manufacture designed to be mounted in different characters of containing casings and comprising a support, a driving shaft mounted in said support, an indicator controlling shaft mounted in said support, speed controlled mechanism operatively connecting said driving shaft with said indicator controlling shaft and means carried \by the unit for fastening the same to any one of the containing casings. a

6. Ina device of the class described, a mechanical unit complete in itself, and provided with means for mounting the same in a containing casing, said unit including a support a driving shaft mounted for rotary movement in said support, a member provided with an annular groove, slidably mounted on said shaft and operatively controlled by the speed thereof, a mounting late removably afiixed to said support, an indicator actuating mechanism supported from said plate and removable as a unit therewith, said mechanism including a rounded head disposed in the annular groove of said sliding member and removable therefrom without disturbing either the mechanism carried by the shaft or the mechanism carried by the late.

7. In a device of the c ass described, a mechanical unit complete in itself and com prising a circular frame provided with means for locating the same in an'inclosing casing, a speed controlled member carried by said frame, a mounting plate removably aflixed to said frame, an indicator actuating mechanism carried by said plate-adapted to be operatively connected to said speed controlled member, parts of said mechanism being adjustable so as to be centrally disposed relative to said-inclosing casing and a dial having a scale curvedabout a center coinciding with the center of said inclosing casing. v

8. In a device of the class described, a containing casing, a frame provided with an end thrust bearing disposed-within the casing, a boss having a threaded bore alined with said bearing and projecting exteriorly of the casing, a thrust bearing adjustably mounted in said threaded bore, a shaft extending through said adjustable thrust bearing and having an end mounted in said end thrust bearing, anti-friction devices disposed between said bearings and said shaft,-

boss from the outside of the casing for taking up wear on the parts and for regulating the longitudinal pressure between the shaft and said anti-friction means.

9. In a device of the class described, a skeleton frame designed to be mounted in an inclosing'casing provided with an end thrust bearlng, a boss having a threaded bore alined with said bearing, a thrust hearing adjustably mounted in said threaded bore, a shaft extending through said adjustable thrust bearing and having an end mounted in said end thrust bearing, antifriction devices disposed between said bearings and said shaft, said adjustable thrust bearing being provided with means accessible through said boss for taking up wear on the parts and for regulating the longitudinal pressure between the shaft and said anti-friction means and means for locking bearing and having an'end mounted in said end thrust bearing, anti-friction devices disposed between sald bearlngs and said shaft,

' said adjustable thrust bearing being provided with means accessible through said boss from the outside of the casmg for taking "up wear on the parts and for regulating the combination of a shaft, a. sleeve slidably mounted on said shaft, the bore of said sleeve havinglongitudinally spaced reduced portions engaging, said shaft and providing an annular pocket therebetween, said sleeve being provided with an air vent leading from said pocket to the outside of the sleeve to permitthe escape of air from said pocket as the sleeve is moved along the shaft.

13. In a device of the class described, the combination of-a driven shaft, a sleeve slidably mountedon said shaft and having a relatively long bearing thereon, means for moving the sleeve along the shaft, means acting on said sleeve intermediate its length tending to twist the sleeve into ibinding engagement with the shaft, thevbore of said sleeve being provided with a pocket inter-- mediate its length thereby to reduce the en gaging surface of the sleeve with the shaft, said pocket being provided with means for permitting the escape of air from said pocket,

14. In a device of the. class described, the combination of a speed controlled member and an indicator actuating mechanism including a shaft, a crank mounted on said shaft, the free arm of said crank engaging said member to be rocked thereby, means for adjusting said crank on said shaft where by to insure an adjustable connection between said member and mechanism, a lever attached to said crank and resilient means acting on said lever to maintain a positive bearingconnection between the free arm of said crank and said member.

15. In a device of the class described, the combination with a speed controlled member, of an indicator actuating mechanism,

comprising a support, a .pair of shafts' mounted for rotary movement in said support, a crank and a segmental rack s aced apart and each fixed to one of said s afts, an indicator and a pinion fixed to the other shaft, said rack meshing with said pinion andthe free arm of said crank operatively connected to said speed controlled member.

16. In a device of the classdescribed, the combination with a speed controlled member, of an indicator actuating mechanism,

comprisin a support, a pair of shafts mounted or rotary movement in said support, a crank and a segmental rack spaced apart and each fixed to one of said shafts, an indicator and 'a pinion fixed to the other shaft, said rack meshing with said pinion and the free arm of said crank operatively connected to said speed controlled member and resilient means engaging said crank to maintain the arm; thereof in engagement with said member.

17. In a device of the class described, the combination with a speed controlled member, of an indicator actuating mechanism, comprising a support, a pair of shafts mounted for rotary movement in said support, a crank and a segmental rack fixed to oneof said shafts and spaced from each other, an indicator and apinion fixed to the other shaft, said rack meshing with said pinion and the free arm of said crank operatively connected to said speed con-.

trolled member and resilient means acting on said pinion to maintain the teeth thereof continually in bearing engagement with the for rotary movement in said support, a crank 7 and a segmental rack fixed to one of said shafts, an indicator 'and a pinion fixed to the other shaft, said rack meshing with said pinion and the free arm of said crank operatively connected to said speed controlled i .019; In a device of the class described, the

combination with a speed controlled member, of an indicator actuating mechanism, comprising a support, a pair of shafts mounted for rotary movement in said support, a

crank and'asegmental rack fixed to one of said shafts, an indicator and a pinion fixed to the other shaft, said-rack meshing with said pinion and the free arm of said crank operatively connected to said speed controlled member and resilient means acting on said pinion to maintain the teeth thereof continually in bearing engagement with the teeth of the rack, said resilient means acting on the pinion and rack in the opposite directions to maintain the teeth of the same in contact. Y

.20. In a device of the class described, the

combination with a speed controlled member, of an indicator actuating mechanism and a support therefor,"said indicator mechanism including two shafts mounted'for r0- tary movement in said support, one of said shafts operatively connected to said speed controlled member to be rotated by the movement of said member, said support having a plurality of bearings, each adapted to support the other shaft, said other shaft constituting a shiftable shaft adapted to move an indicator, and a driving connection between said shafts operable in all positions of said shiftable shafts.

21. In a device of the class described, the combination with a speed controlled'member, of an indicator actuating mechanism and a support therefor, said indicator mechanism including two shafts mounted for rotary movement in said support, one of said shafts operatively connected to said speed controlled member to be rotated by the movement of said member, said support having a plurality of bearings, each adapted to support the other shaft, an indicator fixed to said other shaft, a scale for said indicator, and a driving connection between said shafts operable in all positions of said shiftable shafts.

22. In a device of the class described, the

combination ofa support which may be subjected to vibration or jerky movements, a driving shaft mounted for rotary movement in said support, a speed controlled member slidably mounted on said shaft, a centrifugally actuated member operated from said shaft and actuating said sliding member, and a loose connection between said centrifugally actuated member and said sliding member, said loose connection including a pivotal mounting for the centrifugally actuated member disposed to the inside of its center of mass, whereby vibratory movement of the support is taken up by said centrifugally actuated member.,

23. In a device of the class described, the combination of a support which may be sub jected to vibration or jerky movements, a driving shaft mounted for rotary movement in said support, a speed controlled member slidably mounted on said shaft, a centrifugally actuated member operated from said shaft and actuating said sliding member,

and a loose connection between said centrif- ;uga1ly actuated member and sa d sliding member and a loose connection between said shaft and said sliding member whereby v1- bratory movement of the support is taken up by said centrifugally actuated member. 24:. In a device of the class described, the combination of a support, which may be subjected'to vibration or jerky movements, a driving shaft mounted for rotary movement in said support, a speed controlled member slidably mounted ,on said shaft, a centrifugally actuated member operated from said shaft and actuating said sliding member, a loose connection between said centrifugally actuated member and said sliding member and a loose connection between said shaft and said: sliding member whereby vibratory movement of the support is taken up by said centrifugally actuated member, said connections having a common point of attachment with said centrifugally actuated member at its inner edge.

25. In a device of the class described, the combination with a speed controlled member, andan indicator actuating mechanism operatively connected therewith, a plurality ofresilient means for resisting the movement of said speed controlled member, means for bringing the different resilient means into operative resisting engagement with the speed controlled member atdifferent speed indicating positions of the indicator actuating mechanism and adjusting means operatively connected to said indicator ac tuating mechanism for calibrating the device whereby the device may be adjusted to fit any prescribed scale of speed readings when different types of said resilient means are substituted.

Signed at New Rochelle, in, the county of W'estchester and State of New York, this 13 day of May, A. D. 1915.

CLARENCE CARSON. 

